Para - Malaria Flashcards
(119 cards)
1
Q
Describe the vector for Plasmodium species responsible for malaria.
A
The vector for Plasmodium species is the Anopheles mosquito.
2
Q
Define the role of the Anopheles mosquito in the life cycle of Plasmodium.
A
The Anopheles mosquito is the definitive host for Plasmodium because it contains the sexual cycle of the parasite.
3
Q
How many species of Plasmodium are mentioned in the content, and what are they?
A
Four species of Plasmodium are mentioned: Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, and Plasmodium falciparum.
4
Q
Explain the difference between the definitive host and the intermediate host in the context of malaria.
A
The definitive host, Anopheles mosquito, supports the sexual cycle of Plasmodium, while the intermediate host, humans, undergoes asexual cycles.
5
Q
Duration of paroxysmal attack of each species
A
Plasmodium vivax causes Benign Tertian Malaria, Plasmodium ovale causes Ovale Tertian Malaria, Plasmodium malariae causes Quartan Malaria, and Plasmodium falciparum causes Malignant Tertian Malaria.
6
Q
How does the life cycle of Plasmodium begin in humans?
A
The life cycle of Plasmodium begins in humans when the Anopheles mosquito injects sporozoites into the bloodstream.
7
Q
Describe the habitat of Plasmodium within the human host.
A
Plasmodium initially resides temporarily inside liver cells and then inside red blood cells (RBCs) during its life cycle.
8
Q
What is the significance of the chimpanzee in the context of Plasmodium species?
A
Chimpanzees serve as a reservoir host (RH) for P. malariae.
9
Q
Explain the term ‘paroxysm’ in relation to malaria.
A
Paroxysm refers to the sudden recurrence or intensification of symptoms, such as fever, associated with malaria.
10
Q
How many asexual cycles occur in the human host during the Plasmodium life cycle?
A
There are two asexual cycles that occur in the human host during the Plasmodium life cycle.
11
Q
Describe the Exoerythrocytic Schizogony Cycle.
A
It occurs inside the liver where sporozoites enter the body through the saliva of a mosquito during a bite, leading to the formation of liver schizonts that contain merozoites.
12
Q
How do merozoites invade red blood cells (RBCs)?
A
Merozoites are liberated from ruptured liver schizonts and invade RBCs, initiating the Erythrocytic schizogony cycle.
13
Q
Define the Erythrocytic schizogony cycle.
A
Merozoites liberated from ruptured liver invade RBCs to become a ring, to a trophozoite, to an erythrocytic schizont containing merozoites.
Erythorcytic schizont ruptures liberating merozoites.
14
Q
What happens to most merozoites after they are released from erythrocytic schizonts?
A
Most merozoites reinvade other RBCs and continue the schizogony cycle, while some form male microgametocytes and female macrogametocytes.
15
Q
Explain the process of gametogony in the mosquito.
A
In the mosquito, male microgametocytes undergo reduction division to form male microgametes, while female macrogametocytes mature into female macrogametes.
16
Q
How is a zygote formed in the mosquito’s gut?
A
Male microgametes fertilize female macrogametes in the lumen of the mosquito’s gut, resulting in the formation of a zygote.
17
Q
Describe the role of the ookinete in the mosquito’s life cycle.
A
The ookinete penetrates the wall of the mosquito’s gut after fertilization, leading to the formation of an oocyst.
18
Q
What occurs within the oocyst in the mosquito?
A
The oocyst contains sporocysts that produce sporozoites, which eventually rupture and are released into the salivary glands of the mosquito.
19
Q
How do sporozoites enter a new host?
A
Sporozoites are introduced into a new host’s blood when the mosquito feeds again.
20
Q
Describe the modes of infection for blood-transmitted malaria.
A
The modes of infection include the bite of an infected female Anopheles mosquito, blood transfusion, congenital malaria, and the use of contaminated syringes.
21
Q
Define the infective stage of malaria when transmitted through a mosquito bite.
A
The infective stage of malaria transmitted through a mosquito bite is the sporozoite.
22
Q
How does congenital malaria occur?
A
Congenital malaria occurs due to placental infarctions or when the umbilical cord is cut.
23
Q
List the infective stages of blood-transmitted malaria.
A
The infective stages of blood-transmitted malaria are Ring, Trophozoite, Schizont, and Merozoites.
24
Q
What is the shape and size of the sporozoite in malaria?
A
The sporozoite is fusiform or banana-shaped and measures 5-15 micrometers.
25
Explain the term 'Transfusion Malaria'.
Transfusion Malaria refers to malaria transmitted through blood transfusions from an infected donor.
26
Identify the infective stage of Plasmodium in mosquitoes.
The infective stage of Plasmodium in mosquitoes is the gametocyte.
27
Do blood transfusions pose a risk for malaria transmission?
Yes, blood transfusions can pose a risk for malaria transmission if the blood is from an infected donor.
28
Describe hypnozoites in relation to Plasmodium vivax and ovale.
Hypnozoites are latent sporozoites that remain dormant inside the liver for years, leading to potential relapse of malaria.
29
Define the significance of stippling in infected red blood cells (RBCs).
Stippling refers to fine or coarse granules that appear in infected RBCs due to cytoplasmic damage caused by the growing parasite.
30
How do malarial pigments form in infected RBCs?
Malarial pigments, such as haematin granules, form inside the cytoplasm of the parasites due to the digestion of hemoglobin.
31
Explain the role of Schuffner's dots in Plasmodium vivax and ovale.
Schuffner's dots are fine stippling observed in infected RBCs specifically in Plasmodium vivax and ovale.
32
Describe the shape of infected RBCs in Plasmodium ovale.
In Plasmodium ovale, infected RBCs have a weak wall and acquire an oval shape.
33
What is responsible for the recurrence of symptoms in malaria due to hypnozoites?
Recurrence of symptoms occurs after cure due to the reactivation of hypnozoites in Plasmodium vivax and ovale.
34
How does Plasmodium falciparum affect the shape of infected RBCs?
In Plasmodium falciparum, infected RBCs may exhibit Maurer's clefts and have a distinct shape compared to other species.
35
Define relapse in the context of malaria caused by Plasmodium vivax and ovale.
Relapse refers to the recurrence of malaria symptoms due to the reactivation of dormant hypnozoites in the liver.
36
Explain the difference in liver involvement between blood-transmitted malaria and other forms.
In blood-transmitted malaria, merozoites released from ruptured erythrocytic schizonts do not invade the liver, resulting in no liver affection and no relapse.
37
Describe the appearance of Ziemann's dots in Plasmodium malariae and ovale.
Ziemann's dots are specific stippling patterns observed in infected RBCs of Plasmodium malariae and ovale.
38
Describe the morphological differences between Plasmodium vivax and Plasmodium falciparum in terms of infected red blood cells (RBCs).
Plasmodium vivax fills 1/3 of the RBC and has a very thin rim of cytoplasm, while Plasmodium falciparum fills 1/6 of the RBC and has a vacuole.
39
How does the appearance of the early trophozoite stage differ between Plasmodium vivax and Plasmodium falciparum?
In Plasmodium vivax, the early trophozoite has a thin rim of cytoplasm and a single ring with 1-3 chromatin dots. In contrast, Plasmodium falciparum has a very thin rim of cytoplasm and 1-2 chromatin dots in the ring.
40
Define the characteristics of the late trophozoite stage in Plasmodium vivax compared to Plasmodium falciparum.
The late trophozoite of Plasmodium vivax has irregular, amoeboid cytoplasm and is not seen in peripheral blood, while Plasmodium falciparum fills the RBC and has compact cytoplasm.
41
What is the structure of the schizont stage in both Plasmodium vivax and Plasmodium falciparum?
Both Plasmodium vivax and Plasmodium falciparum schizonts contain 12-24 merozoites and clumped malarial pigments, and neither is seen in peripheral blood.
42
How do the male microgametocytes of Plasmodium vivax and Plasmodium falciparum differ in appearance?
The male microgametocyte of Plasmodium vivax is rounded with diffuse chromatin, while that of Plasmodium falciparum is crescentic with diffuse chromatin.
43
Describe the female macrogametocyte characteristics in Plasmodium vivax versus Plasmodium falciparum.
The female macrogametocyte of Plasmodium vivax is rounded with compact chromatin, whereas in Plasmodium falciparum, it is crescentic with compact chromatin.
44
What changes occur in the infected RBCs of Plasmodium vivax and Plasmodium falciparum?
Infected RBCs in Plasmodium vivax become enlarged, while those in Plasmodium falciparum remain unchanged.
45
Define Schuffner's dots and Maurer's clefts in the context of Plasmodium species.
Schuffner's dots are stippling seen in Plasmodium vivax, while Maurer's clefts are associated with Plasmodium falciparum.
46
Describe the cause of a malarial paroxysmal attack.
A malarial paroxysmal attack is caused by the rupture of erythrocytic schizonts, leading to the release of toxins, pigments, debris, and pyrogens.
47
Define Tertian Malaria and its occurrence in different Plasmodium species.
Tertian Malaria occurs every third day and is associated with Plasmodium vivax and Plasmodium falciparum.
48
Explain the paroxysm occurrence in Plasmodium malariae.
In Plasmodium malariae, paroxysm occurs every fourth day, which is referred to as Quartan Malaria.
49
How does Plasmodium falciparum affect red blood cells (RBCs) in terms of sequestration?
Infected RBCs with Plasmodium falciparum trophozoites and schizonts adhere to endothelial cells of blood vessels due to the presence of PFEMP-1, leading to sequestration in vital organs.
50
What is the role of PFEMP-1 in Plasmodium falciparum infections?
PFEMP-1 is a specific protein on the surface of infected RBCs that facilitates their adherence to endothelial cells, contributing to the sequestration of these cells in the vascular beds of vital organs.
51
Describe the phenomenon of rosetting in Plasmodium falciparum infections.
Rosetting occurs when infected RBCs adhere to uninfected RBCs, forming large clumps that restrict microvascular flow to vital organs.
52
How does the irregular paroxysm in Plasmodium falciparum differ from other species?
In Plasmodium falciparum, paroxysm can occur every third day or irregularly due to the lack of synchronicity in the rupture of erythrocytic schizonts.
53
Describe the stages of a paroxysmal attack in parasitology.
The stages include: Cold Stage (0.5-1 hour), where the patient feels cold; Hot Stage (4-6 hours), characterized by fever, headache, hot dry skin, and flushed face; and Sweating Stage (1-2 hours), where there is a decrease in temperature and headache, along with shivering, nausea, vomiting, rapid pulse, and exhaustion.
54
How does hemolytic anemia occur in parasitology?
Hemolytic anemia occurs due to the destruction of a large number of red blood cells (RBCs), leading to a reduction in hemoglobin levels.
55
Define jaundice in the context of parasitology.
Jaundice is a condition characterized by yellowing of the skin and eyes, resulting from hyperbilirubinemia due to the destruction of RBCs and the release of bilirubin from ruptured cells.
56
What causes an enlarged liver and spleen in parasitic infections?
Enlarged liver and spleen occur due to the hyperplasia of the reticuloendothelial system (RES) after it engulfs merozoites and pigments from ruptured RBCs.
57
How does Plasmodium falciparum affect anemia severity?
Anemia is more severe in Plasmodium falciparum infections due to heavy parasitemia from the release of large numbers of merozoites, the invasion of all ages of RBCs, and the rupture of both infected and non-infected RBCs, leading to autoimmune hemolysis.
58
Describe the symptoms associated with the hot stage of a paroxysmal attack.
During the hot stage, symptoms include fever, headache, hot dry skin, and a flushed face.
59
What are the symptoms experienced during the cold stage of a paroxysmal attack?
In the cold stage, the patient experiences shivering and a feeling of cold.
60
How long does the sweating stage of a paroxysmal attack last?
The sweating stage lasts for 1-2 hours.
61
What is the significance of rapid pulse in parasitic infections?
A rapid pulse can indicate the body's response to fever and systemic stress during a paroxysmal attack.
62
Describe the complications associated with Plasmodium falciparum infection.
Complications include high parasitemia, invasion of all ages of red blood cells (RBCs), hemolysis of infected and non-infected RBCs, and ischemia due to vessel plugging by infected RBCs.
63
How does Plasmodium falciparum differ from P. vivax and P. malariae in terms of RBC invasion?
P. falciparum invades all ages of RBCs, while P. vivax and P. ovale invade only young RBCs (reticulocytes), and P. malariae invades only older RBCs.
64
Define cerebral malaria and its symptoms.
Cerebral malaria is characterized by loss of consciousness and rapid coma, often resulting from severe complications of P. falciparum infection.
65
What gastrointestinal disturbances can occur in severe cases of malaria?
Severe cases of malaria can lead to gastrointestinal disturbances such as dysentery and profuse diarrhea.
66
Explain the congenital complications of malaria.
Congenital complications include blockage of placental sinusoids leading to anoxaemia and infarctions in the placenta, as well as the passage of infected RBCs from mother to fetus, resulting in congenital malaria.
67
How does high parasitemia affect the severity of P. falciparum malaria?
High parasitemia results from the release of 40,000 merozoites from each liver schizont, leading to severe manifestations and mortal consequences.
68
What is the significance of autoimmune hemolysis in P. falciparum infections?
Autoimmune hemolysis occurs due to the destruction of both infected and non-infected RBCs, contributing to the severity of the disease.
69
Describe the process of ischemia in the context of P. falciparum malaria.
Ischemia is caused by the plugging of vessels in vital organs by masses of infected RBCs due to sequestration and rosetting, leading to tissue damage.
70
Describe the renal affection caused by Plasmodium falciparum.
Plasmodium falciparum can lead to malarial nephrosis characterized by tubular damage, black water fever, and severe intravascular hemolysis, resulting in hemoglobinuria and acute tubular necrosis.
71
Define malarial nephrosis.
Malarial nephrosis is a kidney condition associated with malaria, particularly caused by Plasmodium falciparum, leading to tubular damage and complications such as hemoglobinuria and renal failure.
72
How does Plasmodium falciparum cause hemolysis in the body?
Plasmodium falciparum causes hemolysis by infecting red blood cells (RBCs), leading to the destruction of both infected and non-infected RBCs, resulting in severe intravascular hemolysis.
73
What is the difference between relapse and recrudescence in malaria?
Relapse refers to the recurrence of symptoms and reappearance of parasites in the blood due to reactivation of hypnozoites, occurring only in P. vivax and P. ovale. Recrudescence is the recurrence of symptoms and parasites due to reactivation of blood stages surviving in small numbers in RBCs, occurring in all types of malaria.
74
Explain the term 'black water fever' in relation to malaria.
Black water fever is a severe complication of malaria, particularly associated with Plasmodium falciparum, characterized by hemoglobinuria and dark-colored urine due to the breakdown of red blood cells.
75
How can repeated infections with Plasmodium falciparum lead to renal failure?
Repeated infections with Plasmodium falciparum, especially with incomplete treatment using quinine, can lead to cumulative damage to the kidneys, resulting in conditions like acute tubular necrosis and renal failure.
76
Define nephrotic syndrome in the context of malaria.
Nephrotic syndrome in malaria refers to a kidney disorder characterized by significant proteinuria, edema, and hyperlipidemia, often associated with infections like those caused by Plasmodium falciparum.
77
What is the role of immune complexes in malarial nephrosis?
Immune complexes in malarial nephrosis are formed due to the deposition of antibodies against red blood cells, leading to kidney damage and contributing to the nephrotic syndrome.
78
Describe the purpose of a thin blood film in parasitology.
A thin blood film is used for easier morphological examination and differentiation between different malaria species.
79
Define the function of a thick blood film in malaria diagnosis.
A thick blood film is used for the easy detection of parasites due to the hemolysis of red blood cells (RBCs).
80
How are samples taken for diagnosing Plasmodium vivax, ovale, and malariae?
Samples are taken during the attack to observe the presence of ring, trophozoite, schizont, and gametocyte stages.
81
What staining methods are used in malaria diagnosis?
Giemsa or Leishman stains are used for staining blood films in malaria diagnosis.
82
Explain the observation for Plasmodium falciparum in blood films.
In cases of Plasmodium falciparum, only ring and gametocyte stages are observed because RBCs infected with trophozoite and schizont are sequestrated in deep blood vessels.
83
Describe the Rapid Malaria Diagnostic Test.
The Rapid Malaria Diagnostic Test detects antigens in circulation and is known for being simple, rapid, sensitive, and highly specific.
84
What is the gold standard method for malaria diagnosis?
The gold standard method for malaria diagnosis involves microscopic examination of blood films.
85
Describe the general measures for treating parasitic infections in blood.
General measures include rest in bed, cold sponging, antipyretics, sedatives for headache, and regulation of fluid intake and salt balance.
86
How should malarial treatment be approached to ensure effectiveness?
Malarial treatment should aim to destroy parasites in the blood to cure the clinical attack, destroy parasites in the liver to prevent relapse, and eliminate gametocytes to prevent transmission.
87
Define the role of Chloroquine in treating Plasmodium vivax and ovale infections.
Chloroquine is a blood schizonticidal drug used to treat infections caused by Plasmodium vivax and ovale.
88
What is the purpose of Primaquine in malaria treatment?
Primaquine serves as a tissue schizonticidal and anti-relapse drug, causing radical cure and elimination of gametocytes.
89
Explain the treatment regimen for Plasmodium falciparum and malariae.
The treatment regimen for Plasmodium falciparum and malariae involves using Chloroquine, as these are classified as non-relapsing malaria.
90
How does the treatment of malaria differ between relapsing and non-relapsing types?
Relapsing malaria, caused by Plasmodium vivax and ovale, requires a combination of Chloroquine and Primaquine, while non-relapsing malaria, caused by Plasmodium falciparum and malariae, typically involves Chloroquine alone.
91
What is the significance of using a combination of drugs in malaria treatment?
No single drug is effective on its own; a combination of drugs is usually used to ensure comprehensive treatment of malaria.
92
Describe the feeding habits of mosquitoes.
Both male and female mosquitoes feed on plant nectar for energy, but only female mosquitoes are blood suckers, as blood meals are essential for the development of their eggs.
93
How do female mosquitoes prevent blood coagulation during feeding?
Female mosquitoes secrete saliva that contains anticoagulants, which prevent the coagulation of the host's blood.
94
Define anthropophilic and zoophilic mosquitoes.
Anthropophilic mosquitoes are those that suck blood from humans, while zoophilic mosquitoes suck blood from animals.
95
Identify the most efficient vector of malignant malaria.
Anopheles gambiae is the most efficient vector of malignant malaria because it is anthropophilic.
96
Name the chief vectors of human malaria in Egypt.
Anopheles sergenti and Anopheles pharoensis are the chief vectors of human malaria in Egypt.
97
Explain the significance of hibernation in mosquitoes.
Hibernation in mosquitoes explains the sudden increase in their numbers during early summer after winter.
98
What are common breeding places for mosquitoes?
Common breeding places for mosquitoes include water collections and rice fields.
99
Describe the life cycle of a mosquito.
The life cycle of a mosquito involves complete metamorphosis, which includes the stages of egg, larva, pupa, and adult.
100
Describe the medical importance of mosquitoes.
Mosquitoes are important as they are causative agents of diseases, cause biting nuisance and allergic dermatitis due to saliva proteins, and serve as vectors for human pathogens, particularly the female mosquitoes.
101
Define the role of female mosquitoes in disease transmission.
Female mosquitoes are responsible for transmitting diseases as they bite and inject saliva containing pathogens into humans.
102
How does Culex transmit Bancroftian filariasis?
Culex transmits Bancroftian filariasis (W. bancrofti) through skin penetration by infective larvae.
103
What diseases are transmitted by Anopheles mosquitoes?
Anopheles mosquitoes transmit human malaria (protozoa) and Malayan filariasis (Brugia malayi).
104
Explain the transmission mode of West Nile viral encephalitis by Culex mosquitoes.
West Nile viral encephalitis is transmitted by Culex mosquitoes through the propagative mode, specifically by inoculation of the virus with saliva.
105
How do Aedes mosquitoes transmit yellow fever?
Aedes mosquitoes transmit yellow fever through the propagative mode, by inoculating the virus with their saliva.
106
List the diseases associated with Aedes mosquitoes.
Aedes mosquitoes are associated with yellow fever and dengue fever, both of which are viral diseases.
107
What is the mode of infection for malaria transmitted by Anopheles mosquitoes?
Malaria is transmitted by Anopheles mosquitoes through the inoculation of sporozoites with saliva.
108
Describe the allergic reaction caused by mosquito bites.
Mosquito bites can cause allergic dermatitis, which appears as red irritating swellings due to the injection of proteins from the mosquito's saliva.
109
Define cyclodevelopmental transmission in the context of mosquito-borne diseases.
Cyclodevelopmental transmission refers to the process where the pathogen undergoes development within the mosquito before being transmitted to the host, as seen in Bancroftian filariasis and Malayan filariasis.
110
What is the significance of the term 'propagative' in mosquito disease transmission?
The term 'propagative' indicates that the pathogen multiplies within the mosquito before being transmitted to the host, as seen in diseases like yellow fever and dengue fever.
111
Describe the control methods for immature stages of mosquitoes.
Control methods include physical (environmental) control, biological control using natural enemies, and chemical control with insecticides.
112
How can physical control be implemented to manage mosquito populations?
Physical control can be implemented by draining and filling small collections of water, increasing slopes of canals to enhance water flow, and modifying natural conditions to make them unsuitable for mosquito breeding.
113
Define biological control in the context of mosquito management.
Biological control involves using natural enemies such as predators like Gambusia affinis fish, which feed on mosquito larvae and pupae, and pathogens like Bacillus thuringiensis bacteria that are toxic to larvae.
114
What role do pathogens play in biological control of mosquitoes?
Pathogens like Bacillus thuringiensis bacteria produce spores that act as endotoxins, which are toxic to mosquito larvae while being safe for humans.
115
How do chemical controls function in mosquito management?
Chemical controls involve using insecticides that can act as respiratory poisons, stomach poisons, or residual insecticides to kill mosquito larvae and pupae.
116
Explain the function of non-volatile oils in mosquito control.
Non-volatile oils create a continuous layer on the water surface, acting as a respiratory poison that causes suffocation and poisoning of mosquito eggs, larvae, and pupae.
117
What is the effect of Paris Green on mosquito larvae?
Paris Green is a green powder that kills surface-feeding Anopheles larvae but does not affect pupae since they do not feed.
118
Define Insect Growth Regulators (IGRs) and their purpose in mosquito control.
Insect Growth Regulators (IGRs) are compounds that inhibit larval development into adults and prevent chitin synthesis in larvae, effectively controlling mosquito populations.
119
Give an example of an Insect Growth Regulator used in mosquito control.
An example of an Insect Growth Regulator is Methoprene, which disrupts the normal development of mosquito larvae.
